[Bug sanitizer/61314] New: Building GCC 4.9.0 breaks in libbacktrace on Ubuntu Lucid Lynx

[Bug sanitizer/61314] New: Building GCC 4.9.0 breaks in libbacktrace on Ubuntu Lucid Lynx

[gk at torproject dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61314

            Bug ID: 61314
           Summary: Building GCC 4.9.0 breaks in libbacktrace on Ubuntu
                    Lucid Lynx
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gk at torproject dot org
                CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
                    jakub at gcc dot gnu.org, kcc at gcc dot gnu.org

When building gcc 4.9.0 on Ubuntu Lucid the build breaks with the following
error:

/bin/bash ./libtool --tag=CC   --mode=compile gcc -DHAVE_CONFIG_H -I.
-I../gcc-4.9.0/libbacktrace  -I ../gcc-4.9.0/libbacktrace/../include -I
../gcc-4.9.0/libbacktrace/../libgcc -I ../libgcc  -funwind-tables
-frandom-seed=dwarf.lo -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -Wold-style-definition -Wmissing-format-attribute
-Wcast-qual  -g -O2 -c -o dwarf.lo ../gcc-4.9.0/libbacktrace/dwarf.c
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I../gcc-4.9.0/libbacktrace -I
../gcc-4.9.0/libbacktrace/../include -I ../gcc-4.9.0/libbacktrace/../libgcc -I
../libgcc -funwind-tables -frandom-seed=dwarf.lo -W -Wall -Wwrite-strings
-Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition
-Wmissing-format-attribute -Wcast-qual -g -O2 -c
../gcc-4.9.0/libbacktrace/dwarf.c -o dwarf.o
../gcc-4.9.0/libbacktrace/dwarf.c: In function 'dwarf_lookup_pc':
../gcc-4.9.0/libbacktrace/dwarf.c:2678: warning: implicit declaration of
function '__atomic_load_n'
../gcc-4.9.0/libbacktrace/dwarf.c:2678: error: '__ATOMIC_ACQUIRE' undeclared
(first use in this function)
../gcc-4.9.0/libbacktrace/dwarf.c:2678: error: (Each undeclared identifier is
reported only once
../gcc-4.9.0/libbacktrace/dwarf.c:2678: error: for each function it appears
in.)
../gcc-4.9.0/libbacktrace/dwarf.c:2738: warning: implicit declaration of
function '__atomic_store_n'
../gcc-4.9.0/libbacktrace/dwarf.c:2738: error: '__ATOMIC_RELEASE' undeclared
(first use in this function)
../gcc-4.9.0/libbacktrace/dwarf.c: In function 'dwarf_fileline':
../gcc-4.9.0/libbacktrace/dwarf.c:2873: error: '__ATOMIC_ACQUIRE' undeclared
(first use in this function)
../gcc-4.9.0/libbacktrace/dwarf.c: In function 'backtrace_dwarf_add':
../gcc-4.9.0/libbacktrace/dwarf.c:3006: error: '__ATOMIC_ACQUIRE' undeclared
(first use in this function)
make[2]: Leaving directory `/home/ubuntu/build/gcc/libbacktrace'
make[2]: *** [dwarf.lo] Error 1

It works fine on Ubuntu Precise. The gcc version on Lucid is 4.4.3 and on
Precise 4.6.3. I configured the 4.9.0 build with --prefix=path/to/my/dir
--disable-multilib --enable-languages=c,c++

[Bug sanitizer/61314] Building GCC 4.9.0 breaks in libbacktrace on Ubuntu Lucid Lynx

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61314

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2014-05-26
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
It looks like the configure check for '__atomic extensions' reports they are
available for you but in reality they are not.  Please provide config.log
from libbacktrace/.

[Bug sanitizer/61314] Building GCC 4.9.0 breaks in libbacktrace on Ubuntu Lucid Lynx

[gk at torproject dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61314

--- Comment #2 from Georg Koppen <gk at torproject dot org> ---
Created attachment 32856
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=32856&action=edit
config.log

Attached is the config.log. Here comes some additional information that might
help to understand this bug. The build failure does not happen when running
|make| but |make install| which is surprising. It might be due to our
deterministic build setup which uses Gitian and libfaketime. We had and still
have a lot of trouble compiling GCC when using libfaketime and what we are
currently doing is compiling GCC with -j1 we seems to avoid the problems
involved in faking the timestamps. Until now. The lines immediately before the
pieces I posted above are:

make[2]: Leaving directory `/home/ubuntu/build/gcc/gcc'
make[2]: warning:  Clock skew detected.  Your build may be incomplete.
make[2]: Entering directory `/home/ubuntu/build/gcc/intl'
make[2]: Warning: File `Makefile' has modification time 0.23 s in the future
make[2]: Nothing to be done for `install'.
make[2]: warning:  Clock skew detected.  Your build may be incomplete.
make[2]: Leaving directory `/home/ubuntu/build/gcc/intl'
make[2]: Entering directory `/home/ubuntu/build/gcc/libbacktrace'
make[2]: Warning: File `dwarf.lo' has modification time 0.035 s in the future

Here is what seems to happen: the build system seems to realize that there
might have been issues in the build and is recompiling dwarf.c during the
make-install-step but not using the compiler the configure was for but the one
Lucid ships. That this is a non-issue for compiling on Precise might be due to
me not compiling 4.9.0 in the Gitian/libfaketime environment. Does this make
some sense? If so, do you see a workaround for us here? Pointing to the
compiler the configure setup was for after |make| ran? Or...?